Samsung appears to be artificially boosting the Note 3's performance in so-called benchmark tests with a special, high-power mode for its central processing unit that kicks in when the device runs a lot of popular benchmarking apps, the blog reported.

Samsung has done this before outside the U.S., but Ars Technica said this was the first time it spotted the activity with a device for the U.S. market.

"Samsung does it again: rigs its Note phone to cheat when running benchmark apps. Deceptive and shameful," New York Times gadget reviewer David Pogue wrote on Twitter.